Improvement in adjustable desks for chairs



S. RIPLEY.

Improvement in Adjustable Desks for (ih airsfc'.

EN0. 132,494. ,4f/6.7., 4Patented Oct. 22, 1872.

iiiTTTnn sTaTns PATENT @Trice SEWALL G. RIPLEY, OF PORTLAND, MAINE.

IMPROVEMENT IN ADJUSTABLE DESKS FOR CHAIRS, &c.

Specication forming part of Letters Patent No. 132,494, dated October 22, 1872.

To all whom it may concern: l

Be it known that I, SEWALL G. RIPLEY, of Portland, in the county of Cumberland and State of Maine, have invented a new and useful Improvement in Adjustable Desks for Chairs, 5cc.; and that the follgwing description, taken in connection with the accompanying plate of drawing, is a full and complete specification of the same.

This invention relates to desks for chairs, Ste., arranged for adjustment at varying angles of inclination 5 and it consists of parts arranged upon or applied to the under side of the deskboard, and constructed to adjust it as desired and for attachment to the chair-frame so as to turn horizontally thereon, as will be hereinafter described.

In the accompanying plate of drawing my improvement in adjustable desks for chairs, 85o., is illustrated, Figure l being a front View of a desk at an angle of inclination, Fig. 2, a side View, Fig. 3, a section. on line z z, Fig. l, Fig. 4, a section on line y y, Fig. 3; and Fig. 5, a section on line a' a', Fig. 3.

A in the drawing represents a desk-board, made in the present instance ofa square shape, and along its front edge B with a projecting strip, C, havingswin ging staples as ordinarily in this class of chair-desks; D D2, two standards or blocks fastened in parallel positions to the under side of the desk-board A and at or near its central portion; E, a shaft, arranged to turn at each end in the standards D D2, its axis being parallel to the desk-board. This shaft E, midway between its bearings, has a radially-projecting arm or pintle, F, that may be either attached to or vmade of one and the same vpiece of metal therewith. G, a sectorwheel near one end of shaft E, and inside of its standard D2 at such end. Wheel G has a series of notches, a, in its periphery or edge. These notches c may be either at equal or unequal distances apart. H, a cylinder, firmly fixed to extension I of the standard D2, and arranged by its central axis radially to the wheel G, with one end in This sectorclose proximity to the wheels periphery and of itself in direction at an acute angle to the under side of the desk A, as shown. Within cylinder H is arranged a stem or rod, f, surrounded by a spring, g, which is confined from escape at one end by a cross-pin, It, of the rod f, and by its other end against and by a head, l, to the cylinder. The stem f passes through the head l and terminates in a handle, m, and by its crosspin lt it is guided in longitudinal slots a ofthe cylinder, one slot diametrically opposite to the other. The stem f, by its end o, engages with the notches a of the sector-v Wheei G, and its arrangement is such that the spring g tends to hold it so engaged until, by pulling it outward, it is released therefromthat is, the notches ofthe wheel. When a desk of the construction described is secured A to a chair by its pintle F it is arranged through a bent arm, as ordinarily, within a socket fastened to the chair-arm, and as shown in Fig. l,

the desk being free to be swung around horizontally, its pintle F being the center or axis of such rotation.

By the construction and arrangement of can be adjusted readily to varying angles of inclination; and, second, that whatever its aforesaid adjustment it-is most firmly and rigidly held, and in a manner capable of successfully resisting and withstanding heavy strains to move or disturb it in the slightest degree.

Having thus described my invention, I shall state my claim asfollows:

The desk A provided with standards D D2, carryingashaft, E, having pintle F and notch a, sector-wheel Gfin combination'with springstem f, applied for action, as and for the purpose described.

The above specification signed by me'this 1st day of October, A. D. 1872.

S. C. RIPLEY.

Witnesses:

EDWIN W. BROWN, ALBERT W. BROWN. 

